Propeller



E. S HICKS PROPELLER Feb. 28, 1939 Filed Dec 6, 1937 Patented Feb. 28,1939 UNITED STATES PATENT OFFICE Elias S. Hicks, Portland, Oreg.

Application December 6, 1937, Serial No. 178,273

3 Claims.

This invention relates to propellers and is particularly adapted to beused in connection with aeroplane and boat propellers, air conditioningfans and even pumps.

I The primary object of the invention is to increase the eiiiciency ofpropeller and fan blades.

It has been found by experimentation that if the trailing edge of apropeller blade is designed to come in line with the center line of thepropeller that a greater efficiency is obtained. It is believed alsothat the reason for this greater efficiency is that turbulence in thewake of the blade is lessened. By actual tests it has been proven thatthese turbulences cause a counter l acting force or drag and that theseforces are lessened by the construction used in my invention, namely,placing the propeller blade completely forward of the center line drawnthrough the center of the propeller.

:0 Due to the construction employed in'my invention the efliciency ofthe propeller or blade is maintained regardless of speed. It is believedthat this is due to the fact that the turbulences or drag have beeneliminated in my construction.

: Referring to the drawing:

Figure 1 is a front elevation of my new and improved fan or propeller.

Figure 2 is a detail fragmentary section view taken on line 2-2 ofFigure 1, illustrating the i0 blades mounted on the hub. 1

Figure 3 is a front detail fragmentary sectional view of Figure 2,showing the mounting" and holding of the blades within the hub.

In the drawing: 35 I, 2, 3 and Mare the propeller or fan blades mountedupon a suitable hub 5. In some instances it is notnece'ssary to have ahub 5 separate from the blades such as would be used in small fan orboat propellers.

The invention resides, I believe in the fact that the trailing edge 6 ofthe blades are approximately in line through the center of the hub. Theforward edge of the blade I should conform in shape and width to therevolutions required of that 5 particular fan. The widths ofthe blademay vary as well as the pitch. The main portion 8 of the blade has adifferent pitch than the portion 9 and here again the proportion of theareas Y relative to each other may be varied depending 50 upon the usesto which the fan may be used. The angle of the blade is changedat 9 andhas the velocity of the air against the face of the blade at l0, Figure2, besides up in the direction of the arrow it causes a pulling actionof the intake air indicated by the dotted arrow which increases theefliciency suction and supply of air similar to a steam injection,therefore the for- 5 ward edge of the blade at I does not have to do allof the work in supplying the air stream.

In the construction shown in the drawing a main hub body 5, has .a slitll cut therein for receiving the ends l2 of the blades. Face plates 1 !3are then clamped on either side of the hub by suitable belts orfastening means M which pass through the ends l2 of blades clamps thewhole in a solid assembly. As stated before the construction of the hubis immaterial but the invention resides in the shape of the bladesincluding the trailing angle relative to the blade. Said trailing anglecreates a greater suction of the air stream at the same time due to thefact that the trailing edge; of the blade does not extend past and isforward the center line of the propeller, eddy or turbulent currents ofair are eliminated permitting a greater intake at all speeds of the airstream that is being forced forward or through the fan or propelleritself.

My invention is adapted to many forms of embodiment and I do not wish tobe limited to the particular form of embodiment shown in the drawing andclaims.

I claim:

1. A fan or propeller comprising a hub having a plurality of bladesattached thereto, each blade having a leading portion and a trailingportion, the leading edge of the leading portion being curved and thefree edge of the trailing portion being on a line passing through thecenter of the hub, the trailing portion being at a plane angle to theplane of the leading portion.

2. A fan or propeller comprising a hub having a plurality of bladesattached thereto, each blade having a leading portion and a trailingportion, the leading edge of the leading portion being curved and thefree edge of the trailing portion being substantially on a line radialof the hub, the pitch of the trailing portion being increased withrespect to the pitch of the leading portion.

3. A construction as defined in' claim 1, wherein the transversedimension of the trailing portion is gradually increased from the hubtoward the free end of the blade; 6 ELIAS S. HICKS.

